An RF power module is a signal amplifying electronic component used in a communication device such as, for example, a cellular phone, or the like. The RF power module is assembled by packaging semiconductor chips, each having signal amplifying transistors, chip parts, and the like, over a module board. The respective semiconductor chips and the module board are electrically connected to one another through bonding wires. Also, the chip parts can be electrically connected to the module board by connecting their terminals to pads of the module board by soldering.
Such a configuration with a bias circuit and a bias switch circuit employed in high frequency power amplifiers for a dual band system constructed of HBTs (Heterojunction Bipolar Transistors), has been disclosed in Japanese Patent Laid-Open No. 2000-332551.
Further, such a configuration that, in high frequency parts or components for a dual band system, includes a plurality of GND lines provided between output microstrip lines to prevent interference between two outputs has been disclosed in, for example, Japanese Patent Laid-Open No. 2001-141756.
Furthermore, a technique for providing ground pads between output pads of both a semiconductor chip and a wiring board to prevent interference between two outputs in a power module for a dual band, and for wire-bonding, has been disclosed in, for example, Japanese Patent Laid-Open No. 2001-345400.